Apparatus for drying wood



(No Model.) 2 Sheets-Sheet 2.

A. STEVENS.

APPARATUS FOR DRYING WOOD.

No. 437,731. Patented Oct. 7, 1890.

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UNITED STATES,

PATENT OFFICE.

ANSEL STEVENS, OF VESTBROOK, MAINE.

APPARATUS FOR DRYING WOOD.

SPECIFICATION forming part of Letters Patent No. 437,731, dated October '7, 1890.

Application filed April 2, 1888- Serial No. 269,390. (No model.)

To all whom it may concern.-

Be it known that I, ANSEL STEVENS, a citizen of the United States, residing at \Vestbrook, in the county of Cumberland and State of Maine, have invented a certain new and useful Improved Apparatus forDrying 00d Designed to be Manufactured into Fiber, which is subsequently reduced to pulp and used in the manufacture of paper, of which the following is a specification.

The object of my invention is to rapidly and evenly dry the wood to be so used without at any time during the process raising the temperature of the wood so high as to injure the fiber for the use for which it is designed.

By the present methods and the apparatus now in use a longtime is consumed in drying the wood, and when the processis carried as far as it can be with safety to one part of the wood a portion still remains notsufliciently dried, making necessary the use of much stronger chemicals than would be needed if the wood were evenly and thoroughly dried, causing thereby an increase of cost and an injury to the quality of the pulp when digested. This object I attain by the use of the following devices, which are illustrated in the accompanying drawings, which are hereby made a part ofthis specification, in which- Figure 1 is a longitudinal sectional elevation of an apparatus embodying my invention. Fig. 2 is an end elevation of said apparatus as viewed from the side on which the drying-cylinder is placed.

Same letters show like parts inboth figures.

At A, Fig. 1, is shown, the receiver, into which the wood to be dried (after being first finely comminuted by chopping) is introduced, and the process of drying is commenced in this receiver. At a a 0/66 a a are shown steam-pipes, which are connected together by the crosspipe 19 at the top, the whole system of pipes being supplied with steam when in use from any convenient source. This receiver A is shaped at the bottom in the form of an inverted cone, and in the apex of this cone is the orifice c, and below this orifice is hung the vibratory sieve B, the end of the vibratory sieve farthest from 0 being lower than the end which comes under the orifice c and overlapping the endless apron O, which runs upon the two cylinders (Z and e, the upper surface thereof running from 0 toward the cylindrical revolving heater D. This revolving cylinder turns on the hollow journals f f, which receive steam or hot air from any convenient part of the heating apparatus, and the endless apron O and the cylinder D both incline at the same angle as the sieve B, as shown. The cylinder D has the ports 9 and h, the contents of the cylinder being received at g and discharged -at h, as hereinafter described.

Underneath the vibratory sieve B and apron G are the steam-pipes '5 and j.

At 76 and Z is shown an agitator, with the projecting stem m. This agitator consists of the bar 7o, from which upward into the mass of chipped wood when the receiver is charged project the teeth Z Z Z, &c., which may have either a revolving or reciprocatory motion, imparted by suitable devices through the projecting stem m. This may be done by any of the devices with which mechanics are familiar for producing such motion.

The operation of my invention is as follows: The chopped wood, or, as it is called in the trade, chips, is put in at the upper end of A, and this receptacle, heated by the pipes a a, &c., begins the work of drying the wood. The sieve B is placed near enough to the point of exit from A at 0, so that no more of the chips will issue than can be disposed of by the sieve, as the chips work downward along the incline of B, being still heated by the pipes 1', thus are constantly taking away from the contents of A, which is as constantly kept filled with the material to be operated upon. A vibratory motion may be imparted to B by acrank motion or by any of the well-known methods of procuring such a motion. From B the chopped wood falls upon the apron O, which is also inclined, as hereinbefore described, and is carried along over the pipes j into the cylinder D. The cylinder D is heated by steam through its hollow journals, as described.

Hot air maybe injected, if desired, into the receiver A at c, or, if desired, the whole process may be conducted by the use of hot air instead of steam.

Those skilled in the art to which this invention relates will understand the necessity of keeping the steam at such a degree of pressure and consequent temperature that no injury shall be caused to the Wood.

It will be seen that this apparatus which I have described keeps the chips in constant motion and constantly at any desired temperature, and the Whole mass is subjected to the same amount of heat in passing through the different parts of the machine, and that the Wood as it emerges will be evenly and thoroughly dry and in the best condition for being converted easily and cheaply into pulp.

While the chipped WOOd. is Working clownward, as hereinbefore described, in the re ceiver A, the agitator by its motion keeps the chipped Wood constantly stirred, so that the whole mass will be thoroughly mixed and subjected to the same amount of heat.

What I claim as my invention, and desire to secure by Letters Patent of the United States, is-

1. In a Wood-drier, the combination of a hopper, an agitator arranged therein. and means for heating the contained material, a

screen located beneath the hopper,-a conveyer arranged to receive the material from the screen, a rotating drum to which the couveyer delivers the material, and means for heating and drying the same as it passes from the hopper over the screen and conveyer and through the drum, substantially as described.

2. In a wood-drier, the combination of the hopper having the agitator k Z and the heating-pipes a Z), arranged therein, the inclined shaking screen B, located beneath the hopper, a traveling conveyer receiving the material from the delivery end of the screen, the inclined drum D, to which the conveyer delivers the material, the heating-pipes 11 j, arranged in proximity to the screen and the conveyer, respectively, and the pipe f, for heating internally the drum D, substantially as described.

ANSEL STEVENS. Witnesses:

J. L. MCCARTHY, H. A. TARR. 

